We have demonstrated that monoclonal antibodies to virus specific T cells are capable of stimulating virus specific immune responses. In our murine model system we find that one such antibody is capable of protecting mice against lethal Sendai virus pneumonia. In our previous studies we have characterized the type of immunity generated by this novel form of immunization. In this proposal we plan to expand our studies of this phenomenon to define the precise requirements for the elicitation of T and B cell immunity as well as defining the characteristics of the T cells and antibody elicited by this form of challenge. These studies should allow us to define the mechanism by which an antibody (given without antigen) leads to virus specific immunity. In addition, by characterizing the responding cells generated we will be able to enhance both our understanding of virus specific T cells as well as the mechanisms involved in regulation of the generation of such cells.